Compositions of matter and use thereof



Patented Apr. 27, 1937 PATENT OFFIE coMPosI'rIoNs or MATTER AND- USETHEREOF James J. Jackson, Woodbury, N. J., assignor to PaulsboroManufacturing Company, Paulsboro, N. 3., a corporation of New Jersey NoDrawing. Application August 20,1935, Serial No. 37,100

2 Claims.

This invention relates to an adhesive composition and more particularlyto adhesive compositions for securing fibrous 'sheet materials inlaminated structures and to such structures, or

for adhesively attaching fibrous materials to a supporting base.

Fibrous sheets of felted, matted, and woven or knitted types are usedextensively in various fields including fioor coverings and wallcoverings and the like for decorative and other pur- -.poses. Fibroussheets are frequently either brought together in two or more layers toform laminate-d articles or they are attached to a supporting base. Inboth cases, it has been difficult to prevent penetration of an adhesiveto the outer surface of a fibrous sheet. In cases .of decorative sheetgoods having printed or other colored designs, certain tints are veryapt to become obliterated by the penetration of an ad- L hesive.

An object of the present invention is to pro- .yide an adhesivecomposition that has no undue tendency to penetrate into a fibroussheet.

A further object is to provide an adhesive composition that forms highlyflexible adhesive films :;.;between sheets in laminated goods, whichfilms I are firm and non-tacky at room temperature.

The adhesive, composition of the present invention comprises essentiallyan asphalt, a pitch,

an asphaltite, and filler material. The asphalt .--used-is preferably apyrogenous asphalt ob- .tained as a residue in petroleum cracking andThe pitch is a pyrogenous residue and the mostsatisfactory pitch and onewhich-is preferred is a vegetable oil pitch. Of the fattyacid pitches,cottonseed pitch is particularly preferred. Linseed pitch may be used insome cases. Pitches from animal fats and oils such as for instancestearine pitch or blends of such pitches with pitches from vegetablefats and oils, pine pitch, coal tar pitch, petroleum pitch, and oxidizedasphalt may in some instances be substituted for vegetable oil pitchsuch as cottonseed pitch but for most purposes cottonseed pitch is foundto be peculiarly satisfactory. For the asphaltite, gilsonites arepreferred.

A cottonseed pitch that has a melting point of 112 to 115 F. and apenetration of 150, has greater ductility than asphalts and is lessaffected by heat and cold or temperature changes. In the formula givenbelow the asphalt used may have a melting point of about 225 F. and apenetration of about 15. This asphalt may be designated as a relativelyhard asphalt yielding a relatively hard final product. A gilsonitehaving a hardness of 2 (Mohs scale), and a softening point of about 340F. (Ring and Ball) is found satisfactory for the purposes set forth.

Various fillers may be employed but the filler that is particularlypreferred and which gives peculiarly highly satisfactory results in allcases, is powdered slate. Other fillers may be used such as asbestosfiber, whiting, barytes and clay but none of these have been found assatisfactory as slate in the particular composition of the presentinvention. One advantage in the use of slate is that better results areobtained by its use in compositions maintained at low temperaturesthanby the use of other fillers.

Omission of any one or more of the ingredients in the mix or omission ofasphalt, or pitch, or the asphaltite, or particularly the filler such asslate, yields products that are not as satisfactory as a. product havingall of the ingredients present. To determine the desirability of theproduct particularly for purposes set forth above, several factors areto be kept in mind. The composition must be capable of being reduced toa thin film; it must have strong adhesive properties; it must not splitreadily or at all particularly when cold for instance at 36 F. or below;and it should be relatively inexpensive. .These requirements areextremely well met in the application of the adhesive product of thepresent invention.

A composition having the following proportions and ingredients ispreferred:

Parts by weight Asphalt 12 Cottonseed pitch 8 Gilsonite 4 Slate flour 24Asphalt (15 to 6 to 24 Pitch (17-30%) 8 to 16 Gilsonite (l-12%) 2 to 6Slate (-55%) 18 to 30 Asbestos, having a lower specific gravity thanslate, is used in much lower proportions as for instance four parts byweight replacing 24 parts by weight of the slate.

Although the adhesive may be employed for other purposes, it has beenfound to be particularly adapted to combining fibrous sheets together inlaminated form. Penetration by the mix is controlled by the use of pitchsuch as particularly fatty acid pitches which have the property offorming a skin and of freezing when coming in contact with a coldsurface. The slate flour also helps to prevent penetration of saturatedor unsaturated sheets. The slate flour also gives the mix body byraising the viscosity so that the pressure of laminating rolls cannotsqueeze the mix ahead and thereby leave no mix between the sheets to act.as an adhesive.

An important property of the adhesive of the present invention is thatit will not stick to cold laminating rolls, but will peel off veryeasily. If a sheet breaks or has a hole in it, the mix on coming incontact with the rolls will not stick to the rolls and therefore willnot render it necessary to stop a machine in order to clean the rolls.Any of the mix that runs over the edges of sheets on the rolls can bepeeled off and no trouble is caused by building up of layers of the mixon the rolls.

Numerous bituminous mixes disclosed in prior publications have beenemployed in manufacturing laminated sheets, but they have generally beenfound to stick to the rolls, which means that the latter must befrequently scraped and then cleaned with solvent. Generally such mixesare soft and sticky at normal temperatures and it is possible to pullthe sheets apart and to find the mix still sticky after long use. Withsuch mixes, sheets are apt to skid over each other when passing throughthe rolls because the mixes are not hard enough. Likewise, when alaminated sheet material is rolled up, if the adhesive mix employed forcombining the sheets is too soft, the outer lamination is apt to slip sothat the laminations are not kept in the same relative positions whenthe sheet material is laid out fiat. Also one lamination may be affectedby moisture or atmospheric conditions more than another lamination asthe result of which there is greater expansion or contraction in onelamination than another. The adhesive employed between such laminationsmust be hard enough to prevent undue skidding of one lamination onanother under all conditions.

The mix of the present invention can be used to coat one side of a sheetof goods. The mix can be poured on a sheet as it passes through squeezerolls and it will not stick to the roll with which it comes into directcontact. A sheet coated on one side with afilm of the mix, can be rolledup within a few feet of the coating machine without sticking to theuncoated side of a sheet. The mix is not sticky or tacky at roomtemperature, but is flexible and when in film form will not readilybreak.

Decorated fibrous sheets, previously saturated, or unsaturated, arereadily laminated with sheets saturated or unsaturated with for instancebituminous or other plastic saturants. The decorated sheet may be of theopen porous type such as Krafelt, for instance, which is made upprincipally of curly or kinked vegetable fibers, and yet the adhesivewill not penetrate to obliterate decorations. The adhesive of thepresent composition permits of printing on paper even as thin asnewspaper with oil paints without discoloring the print paint.

The composition of the present invention may have a melting point withina Wide range, particularly from about to 225 F. The melting point of thecomposition is not as important, however, as the proportion ofingredients. The mix may be applied in a liquid state at about 420 F.When the mix reaches room temperature, it is necessary for thesuccessful manufacture of the laminated sheets that the mix be hard,non-tacky, and yet flexible.

Although fatty acid pitch has been mentioned as one of the ingredients,it has been found that in some cases a non-drying oil can be substitutedfor the pitch with some degree of success. One formula that may be usedis as follows:

Parts by weight Asphalt 19 Non-drying oil 1 Y Gilsonite 4 Slate flour 24Non-drying oils such as olive oil, cottonseed oil, and castor oil may beemployed in the above formula.

The above formula is not to be preferred and is not as serviceable as acomposition in which the pitch is used.

I claim:

1. A plastic adhesive composition that will not

